Speaker for the phone from a plastic bottle and a motor

For the speaker, we need the neck of a plastic bottle, a standard plug with a wire and a small motor. The motor should be disassembled in order to get the copper winding and magnet that we need in the process.

Winding a copper wire ideally needs a turn to a turn and it is desirable to calculate its resistance, so if you make such a speaker "by eye" do not abuse long-term use.